Sudoku Puzzle Book 5: 400 Extreme (Very Hard) Sudoku (Paperback) (ISBN-13: 9781987782936)

Sudoku (also known as "Number Place") is a placement puzzle. The puzzle is most frequently a 9 x 9 grid made up of 3 x 3 subgrids (called "regions"). Some cells already contain numbers, known as "givens." The goal is to fill in the empty cells, one number in each, so that each column, row, and region contains the numbers 1 through 9 exactly once. Each number in the solution therefore occurs only once in each of three "directions," hence the "single numbers" implied by the puzzle's name.

Author: Mindful Puzzle Books
ISBN-10: 1987782933
ISBN-13: 9781987782936
Publisher: Createspace Independent Publishing Platform
Language: English
Published: 04/13/2018
Pages: 232
Format: Paperback
Weight: 0.70lbs
Size: 9.00h x 6.00w x 0.49d